Thread-cutting device.



R. L. LYONS.

THREAD CUTTING DEVICE.

APPLICATION Hum DEC.2. 1915.

1,246,965. 7 Patented Nov. 20, 1917.

2 SHEETS%HEET 1.

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ROBERT L. LYONS, 0F WALTHAM, MASSACHUSETTS, ASSIGNOB. TO THE FREDERICK OSANN COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

THREAD-CUTTING DEVICE.

Specification of Letters Patent. Patented Nov, 20, 19197;

Application filed December 2, 1915. Serial No. 64,738.

To all whom it may concern Be it known that 1, ROBERT L. LYONS, a citizen of the United States, and a resident of iValtham. in the county of MiddleseX and State of Massachusetts, have invented certain new and useful Improvements in Thread-Cutting Devices, of which the fol lowing is a specification, reference being had ing machine that the cutter element shall be positively moved to a position out of the,

path or paths of the stitch forming device or devices at the initial operation of the machine and before either ofthe stitch forming devices can strike the cutter element.

-Another object of the invention is to improve the construction of the thread cutter and its operating means.

Other objects of the invention will appear from the following description.

The invention consists in the novel construction of the thread cutter device and its operating means and the combination therewith of the novel retractor or protector device.

The invention also consists in the means for preventing the accidental or unauthor- I ized operation of the cutter element at times.

The invention also consists in such other novel features of construction and combination of parts as shall hereinafter be more fully described and pointed out in the claims. 1

Figure 1, represents abottom plan view of parts of a sewing machineof known construction having the new improvements in thread cutting mechanism applied thereto.

Fig. 2, represents a cross sectional view of parts of the same as taken on line 2+2 7 Fig. 1. r

on line 44 Fig. 1, and showing a loopv of thread on the looper.

Fig. 5, represents a similar view taken on line 55 Fig. 1. 7

Similar characters of reference designate corresponding parts throughout.

As shown in the drawings, in its preferred form. 6 represents the bed plate of a sewing machine of well known construction and of the variety known as a single thread machine but it is not intended by such showing necessarily to limit the use of the present invention thereby. This bed plate 6 has the needle passage 7 and, at its under side is supplied with thelongitudinal members 8, 8 and with the transversely extending mem bers 9 and 10. Journaled' in a bearing of the member 9 is the looper shaft 11 which operates the usual looper 12, located beneath the needle passage 7, and said looper shaft 11 is driven in any well. known .manner through connections withthe worm shaft 13 journaled in a bearing of member 10 and operated in the manner well known in this class of machines.

the worm 14 and the protector disk or meniber 15 which latter is substantially circular in peripheral shape. but has, cut out of its peripheral portion, the notch 16 having the straight edge 17 and the inclined edge 18 in the nature of a cam which merges into the circular periphery of this disk as is shown in Fig. 2, the direction of rotation of this disk being indicated by its arrow. Journaled on the stud 19 secured to the underside of bed plate 6, is the disk 20 having the gear mem er 21 which is driven from the worm 14. This disk 20 has a circular periphery or path 22 having at one point he depression or clearance 28 the pur pose of which will be hereafter explained.

At the under side of the bed plate 6 is the stud 21 on which is pivoted the cutter operating and controlling lev r 25 which has the slot 26 at its free end. Mounted on this lever 25 is the member 27 having the follower or rider rod 28 adapted to ride against the peripheryfor way 22 of disk 20 during 4% which in one direction certain operations of the machine and with which the clearance 9.3 of said disk is brought into registry at or about the time the rotation of the looper 12 ceases as will. hereafter be described.

Adjacent the free end of lever is mounted, at the under side of bed plate 6, the casing 29 which has the slot 30 and the way 31 in which the cutter slide 32 is slidable, said cutter slide is pressed. in one direction by its spring 33 and may be actuated in the other direction by the lever 25 with which said slide is connectedby means of its pin 32 secured in said slide, extending through slot 30 and engaged in slot 26 of said lever. Un said slide 32 is mounted the cutter me 'uber 34 having the cutting blade 35 of slghtly hook shape and having cutting edges (1. b and 0 said blade 35 being adapted to be moved between the bed plate 6 and the looper 12 when said looper extends approximately parallel to said bed piate as is shown in Fig. l of the drawi gs.

Slidably mounted with respect to the bed plate 6 is the rod 36 which may be depressed at times by means of the connection 3'! adapted to be operated in any desired manner to, at times, feet the depression of said rod 36 to cause the swinging of its related bell crank 38 which is pivotally sustained by the stud 39, extending from one of the bed plate members 8, and pivotally connected with the cutter actuator 40.

The cutter actuator l0 has the bevel end. 41 and the depressions or reduced portions 42 and :3 of which the former is adapted to afford clearance for shaft 13 while the latter depression is adapted to receive the cutter actuator lever 25 and has the shoulder of movement of actuator may engage and move said lever 25 under certain positions of the mechanism. This actuator 40 is slidable in a direction transverse to the lever 25 and is normally 7 sustained by the spring 4-5 r'or the'purpose of effecting engagement of the depression 13 with said lever 25 and to permit, at times, the disengagement of these parts, such disengagementis accomplished, under moveiment of said actuator 40, in one direction, by the riding of its cam member 46 over the cooperating cam member 4? mounted on any suitable part of the machine.

Under normal conditions. of the stitch forming operation of the machine to form a group ofstitches the cutter member 3t will preferably occupy the pos1t1on shown in full lines in Fi 1. At the completion of such sewing or stitch forming operation the thread will extend as a loop L having thearms.a2,-;z ,.sustained in part by thelooper 12111116. ,extendingupward, the arrow being in the epath informed as is usual in thi's'cl'ass' -or ma-- of .theedge .0 of the cutter '3 andprefer-ably. the thread will have the k110i; 5

nae-sees 14- of'said actuator may engage with and move said lever 25, such movement being permitted because of the fact that notch 16 of disk 15 is position d to receive said lever 25 and that the clearance 23 of disk 26 is in position to receive the rider 23.

Such swinging movement of lever effects the sliding movement of the slide 32 and its cutter member 34 against the action of spring with the result that the edge 0 of the cutter is drawn against the arm a; of the thread loop L and may out said arm. If, however, said arm cc of the loop is not cut by edge 0 on such retractive movement of the cutter member 3-1- said edge 0 rides against and passes said loop arm cc and the cutter 3 is brought approximately to the position shown in dotted lines in Fig. 1. At or about this time the cam block 46 riding against its cooperating member 47 effects the forcing downward of the free end of the actuator 40 to disengage the depression 4L3 of said actuator from lever 25 whereby said lever is free to be swung to its original position by or through the action of spring 33 in which movement the cutter member 3% is carried forward and the edge a of-its cutter engages and cuts the loop arm m.

After the release of actuator 40 from lever 25 rod 36 is permitted to slide upward and. spring is then allowed to draw said actu ator to its normal position to again receivelever 25 in as depression d3.

Ordinarily the action of spring 33 will be sufficient to return slide cutter memher 3% and lever 25 to the position shown in full lines in Fig. 1. and it is desirable that the cutter member 34: should reach such position or at least be moved to a position out of reach of the looper 12 before the looper has, in the next sewing operation, rotated to a point to strike the cutter 35 of said member If, therefore, the action of spring 33 has not moved its slide 32 and,

safe p0v I ofnotch 16 ofthe 'pro'tector'disk15. In this event. when'the machine is again started, the ll$K '15 will rotate with the shaft 13 in the direction indicated by-"the arrow-of'said disk and the tam 'edge18-"tliereofv'ill ride against'the lever ward until the edge of said lever 25 is clear 2d and move said lever'out-'=f of the periphery of the disk 15. 'This posi tive movement of lever 25 is effected during a partial rotation of shaft 18 with the result that the slide 32 is actuated and cutter member 34 is moved to the safe position before the looper 12 rotates sufficiently to strike the cutter 35.

By reference to Fig. 1. it will be noticed that disk 15 is of smaller diameter than the disk 20, the purpose of disk 15 being pri marily, by means of its cam edge 16, to effeet a quick safety or resulting movement of lever 25, to move cutter member 34 to the safe position, and then to sustain such lever 25 in such position by the riding of the periphery of disk 15 against the edge of said lever, until disk 20 has been rotated sufliciently to carry its clearance 23 out of registry with the rider pin 28, theperiphery 22 of this disk-20 then constituting a path or way to sustain this rider pin 28 throughout the sewing operation as the sewing operation is intended to be completed during a. rotation of disk 20 or at least before its clearance 23 is again brought into registry with the rider p n 28. By this construction the unauthorized or accidental swinging of lever 25 to effect movement of the cutter member 34 or its cutter 35 into the path of the stitch forming devices during-the operation of said devices is prevented.

It is obvious that the means for actuating lever 25 from its position of safety may differ considerably from the actuator 40 and also that said lever actuating means need not necessarily be adapted to be manually operated.

While I have herein shown a specific construction of my improved safety cutter mechanism it is not my intention thereby to limit my invention except as herein claimed.

Having thus described my invention I claim as new and desire to secure by Letters latent.

1. A sewing machine comprising in com bination with a stitch forming device having alooper and means for operating said device, a thread cutter mounted for movement into the path of movement of said looper, and means operating relative to said stitch forming device to move said cutter to a pointof safety during the initial stitch forming movement of said looper.

2. A sewing machine comprising in combination with a stitch forming device having a looper and means for operating said clevice, a thread cutter mounted for movement into" the path of movement of said looper, means to actuate said cutter and means operating relative to such looper to prevent the operation of said cutter during the operaticn of said looper.

3. A sewing machine comprising in combination with a stitch forming device having a looper and means for operating said hold back to prevent the movement of said hold back during certain operations of said looper. 4-. A sewing machine comprising in combination with a stitch forming device having a looper and means for operating said device, a thread cutter mounted for move ment into the path of movement of said looper, means actuated by said operating means to move said cutter to the safe position, and other means in operative connection with said operating means to prevent the operation of said cutter approximately throughout the sewing operation.

5. A sewing machine comprising. in combination, a stitch forming device adapted to sustain a thread loop, a cutter member mounted for movement to cut said loop, a lever for operating said cutter, means for positively moving said lever in one direction, and other means for positively holding said lever in position when so moved, said lever moving means and lever holding means operating relatively.

6. A sewing machine comprising. in combination. a rotary looper, an operating shaft therefor, a member carried by said shaft and having a cam, a cutter mounted for movement relative to said looper, cutter operating means in operative relation to said cam, and means to prevent the retractive movement of said cutter operating means during a series of rotations of said looper.

7. A. sewing machine comprising, in combination, a rotary looper, an operating shaft, connections for operating said looper from sa d shaft, a thread cutter member, a piV- oted lever for operating said cutter memher, and a disk mounted on said operating shaft and having a notch to receive said lever and cam for effecting movement of said lever from said notch.

8. A sewing machine comprising, in comhination, a rotary looper, an operating shaft, connections for operating said looper from said shaft, a thread cutter member, a pivoted lever for operating said cutter memher, and a pair of rotarv members operated by said shaft, one of said members having a notch to receive said lever and a cam to effect movement of said lever out of said notch, the other said member cooperating with said lever to hold the same in an in.- operative position.

9. A sewing machine comprising, in combination, a rotary looper, an operating shaft, connections for operating said looper from said shaft, a thread cutter member, a pivoted lever for operating said cutter member, a rider device carried by said lever,-and

a pair of rotary disks of different diameters, the smaller of said disks mounted on said shaft and having a notch to receive said lever and the larger of said disks, driven from said shaft having a way against which said rider may bear.

10. A. sewing machine comprising, in combination, a rotary looper, an operat ng shaft, connections for operating said looper from said shaft, a thread. cutter member, a pivoted lever for operating said cutter member, a rider device carried by said lever, a pair of rotary disks of different diameters, the smaller of said disks mounted on said shaft and having a notch to receive said lever and the larger of said disks, driven from said shaft having a Way against which said rider may bear, and a clearance to receive said rider at times.

11. A sewing machine comprising, in combination a rotary looper, an operating shaft, connections for operating said looper from sad shaft, a thread cutter member, a pivoted lever for operating said cutter member, a rider device on said lever, a rotary member driven from said shaft and having a pcripheral Way against which said rider may hear and a clearance to receive said rider at times, and means to operate said lever.

12, A sewing machine comprising, in comfiepies of this patent may be obtained for bination a rotary looper, an operating shaft, connections for operating said lcoper from said shaft, a thread cutter member, a pivoted lever for operating said cutter mem her, an actuator member releasably engaged With said lever, means positively to return said lever to position When disengaged from said actuator, and other means positively to prevent the operation of said lever during;

the sewing operation.

13. A seivlng machlne comprising, in combination, a rotary looper, an operating shaft,

connections'fcr operating said looper from sa d shaft, a thread cutter member, a'plv- ROBERT L. LYONSP five cents each. by addressing the Commissioner of .Patents Washington, D. C.

oted lever for operating said cutter mem- 

